[Project Miata] Heat, Roll, Crack the Paint

Sunday evening is the time when most people ready themselves for the work week ahead. Maybe it’s watching a bit of television, or having a nice relaxing dinner. Then there’s the people that can’t stay off the internet…probably because they have nothing better to do.

Half Asleep in the Rain with Shorts

Falling into the latter category, I was surfing good old Craigslist looking for oddball cars and parts. Not expecting to find anything great, I glanced over the wheels & tires section until I came across a relatively rare set of 4 lug BBS wheels. The listing was worded a bit strange, but I had a hunch these were the “dished” 15×7 wheels I had been wanting for quite a few years now. I picked up the phone and the man selling them said they were still available if I wanted to see them that night. I grabbed my rain jacket and flashlight, then off to the ATM I went.

Once I had arrived at my destination, the man selling the wheels turned out to be an older guy with a small collection of vintage BMWs. The wheels checked out and I handed him the money. I knew very well that if I didn’t pick them up that rainy night, they would have been sold long before I could see them the following evening.

Swooped of the Prize

So, what makes these wheels so special? They’re BBS RZ378, meaning they’re 15×7 inch 4 lug wheels with a nice helping of dish. They’re a direct bolt on for the e30 BMW, but other cars with the 4×100 bolt pattern can use them as well. Initially I was hoping to put them on the red 318is, but a certain individual thought they’d look pretty rad on his Miata. I wasn’t entirely thrilled that my sweet Craigslist score was going to be immediately confiscated by Lt. Jim Dangle, but the wheels would have most likely sat before I ever got around to using them. As they say, it’s the cobbler’s children who have no shoes.

It took a few years, but I finally came across a set locally.

BBS RZ378: 15x7in, 4×100, with a 20mm offset.

A nice helping of dish…tasty.

Since the Miata recently got a new set of tires put on its OEM wheels, we needed to swap them over. Looking like a new arrival at Pick-N-Pull, the Miata was stripped of its wheels and put on jack stands. As long as Loma Prieta didn’t make a return visit, the car wasn’t going anywhere. The next day, Miltyman brought both sets of wheels to a tire shop and had the new tires mounted on the new-to-us wheels.

Having had previous experience with BMW wheels, I knew there were a few preventative measures to be taken before the little Mazda could actually drive on these wheels. The first item was to get hub centric rings, since the Miata center bore is 54.1 mm, while the BMW/VW 4 lug wheels are 57.1 mm. Not to worry, they’re all of 12 dollars on Amazon…and that’s if you get the fancy metal ones. The other purchase was for sheer aesthetics. In order to clear the BBS center cap, the lug nuts need to have a relatively low profile. The stock Miata lug nuts have a 19mm head, so they’re too wide to clear the caps. We ended up getting a set of BMW 17mm lug nuts with the same thread pitch to solve the issue.

Here’s the front end in the process of being rolled. I think we can officially give Kyle his fender roller back after 3 years.

Looks like the angry mechanic rushed to the finish line. You can see the paint cracked on the lower lip of the fender. Time for a bottle of touch-up paint.

An inch wider and 25mm offset difference really filled out the fenders nicely.

“Those 195 tires look so meaty!”, said no one ever.

With the wheels finally mounted and the car back on the ground, things were looking good (especially in that oh-so-80s gold). Naturally we wanted take a spin on the new rollers. I think we made it all of two blocks before the rubbing commenced. It appeared the angry mechanic had made a slight miscalculation. Stock wheel offset for Miatas tend to be in the 30-45mm range, while our latest BBS wheels were spec’d at only 20mm, which is why they have as much dish as they do. Looks like the fender roller was coming out of retirement.

Discount Auto Body

A day and a battered ego later, I came back to the battle with both the fender roller and its trusty sidekick, the heat gun. The idea is simple: with the wheel removed, attach the fender roller and gently massage the inner lip of the fender to the point it no longer makes contact with the tire. The trick being to heat the paint so it can flex with the metal of the fender. Pretty straight forward if you ask me.

I started with the rear fenders and managed to get them rolled fairly quick. Then I moved on to the front fenders where I had to make an executive decision. In order to properly roll the front fenders, I had to remove the fender liners which would no longer fit correctly once the fender was rolled. The problem with keeping them permanently removed is that rocks and dirt will collect inside the fender wells. The compromise I decided on was chopping off the front half of the fender liners, that way there are no clearance issues, while road debris will be kept out of the fenders. I’m sure there were better solutions, but I was too busy wondering why Mr. Miata was taking so long to get our takeout.

I was 75% done when the voice of Keanu Reeves told me, “We went too far!” And just like that, I cracked the paint on the last fender. Thinking I had my technique down pat, I didn’t notice that the clock had struck a quarter past amateur hour. At this point I had no choice but to continue. The damage was done though.

Despite the cosmetic upset I had made to the paint, the fender rolling was functionally successful. Around corners, bumps, and dips, the car no longer rubs, and the extra width wheels give the Miata a more aggressive look. The downside is that these BBS RZ wheels are noticeably heavier than the OEM Mazda BBS wheels. Oh, and the chipped paint on the left front fender.

Milton’s the man, with the Midas Touch.

Here you can see the paint mismatch. the car needs a paint job either way. I say keep it the stock color, while Milton wants British Racing Green.

The money shot.

There’s a part of me that thinks this project wasn’t really worth the time and effort, especially since there’s no functional improvement with these wheels, aside from the bling factor. I’d be lying though if I said things always go to plan. Until now, the Miata has been a fairly trouble-free car to work on, so inevitably there would come a day that I’d get tripped by an obstacle. Do I feel bad about ruining part of the paint on Milton’s car? I think so, which is why I ordered a bottle of touch up paint. However, when the color blind guy can see that car is three different shades of blue-green, that’s when you know there’s a bigger elephant in the room.

-JC

Want to put BMW or Volkswagen style BBS wheels on a Miata? Here’s what we used: